Showing 2 results for Energy.
H. Golbakhshi, M. Namjoo,
Volume 5, Issue 2 (6-2015)
Abstract
The viscoelastic effect of rubber material on creation of rolling resistance is responsible for 10-33% dissipation of supplied power at the tire/road interaction surface. So, evaluating this kind of loss is very essential in any analysis concerned with energy saving. The transient dynamic analysis for including the rolling effects of the tire requires long CPU time and the obtained results are prone to considerable numerical oscillations. By adding the equivalent loads to static interaction of tire with the road, an efficient 3D FE analysis is presented for evaluating the dissipated energy of a rolling tire. The results closely match the related experimental and numerical investigations.
Gaurav, R. Kumar,
Volume 5, Issue 3 (9-2015)
Abstract
Air conditioning refrigerant R134a has value of global warming potential (GWP) 1300, which is much higher than MAC Directive (GWP below 150) passed in July 2006. This prompted a search for alternative refrigerant with GWP value less than 150. R1234yf is a new refrigerant which has lower GWP value of 4. Effect of blower speed has been compared and flammability issue of R1234yf has been addressed. Cooling time and relative humidity of car air -conditioning system using refrigerant R134a and R1234yf has also been discussed. The paper discusses various aspects for the replacement of R134a and provides a long term sustainable substitute of presently used refrigerant R134a in automobile air-conditioning.
